Gov. Bruce Rauner outlines his agenda after being sworn into office on Jan. 12, 2015, in Springfield, Illinois. Rauner is the first Republican governor in Illinois since 2003. (Credit: CBS)

CHICAGO (AP) — Illinois labor unions filed a lawsuit Thursday seeking to invalidate Gov. Bruce Rauner’s executive order ending a requirement that state workers pay union dues even if they don’t want to join a union.

Illinois AFL-CIO and 26 unions sued the Republican governor, saying the order he issued last month violates collective bargaining agreements and state labor law and that Rauner exceeded his constitutional authority. The lawsuit filed in district court in St. Clair County also asks a judge to issue an injunction preventing the order from being implemented.

Illinois AFL-CIO President Michael Carrigan said Rauner’s action strikes at more than 40,000 firefighters, snowplow drivers, nurses and other employees who provide critical state services.

“Governor Rauner’s political obsession with stripping their rights and driving down their wages demeans their service, hurts the middle class and is blatantly illegal,” Carrigan said in an emailed statement.

Rauner spokesman Lance Trover said the lawsuit was expected.

“These forced union dues are a critical cog in the corrupt bargain that is crushing taxpayers, and the government unions will do anything to keep the broken status quo,” he said.

Rauner’s order would eliminate so-called “fair share” dues — those dues non-members covered by collective bargaining agreements pay to cover the cost of bargaining, handling grievances and other non-political activities from which all workers benefit.

Rauner also filed a federal lawsuit against the unions. He wants a federal judge in Chicago — and ultimately the U.S. Supreme Court — to declare fair-share dues unconstitutional, saying all union activities are inherently political and making non-members contribute violates their First Amendment rights.

He ordered that the dues, which are paid by about 6,500 workers, be held in escrow while his lawsuit plays out in court. That would keep an estimated $3.75 million from being directed to unions.

In their lawsuit filed Thursday, labor unions argued the money is needed to cover the cost of collective bargaining, handling grievances and communicating with members.

They also said the unions had filed grievances Thursday with the state, claiming Rauner’s order violates collective bargaining agreements that allow the fair-share dues.

Rauner’s executive order, which circumvented a Democrat-controlled Legislature that’s long been supportive of organized labor, is just one of the steps he’s taken against public-employee unions since taking office in January.

He’s repeatedly said the unions have contributed to Illinois’ serious financial problems. He also has accused government union “bosses” of a conflict of interest and has said he wants to make campaign contributions from public-employee unions illegal.

The first-time public office holder and former businessman also has pushed for “right-to-work zones,” or areas of the state where local voters could decide whether employees must join a union as a condition of employment. He says such zones would help Illinois compete with other states that have implemented right-to-work statewide, such as Indiana and Michigan. Neighboring Wisconsin also is moving toward becoming a right-to-work state.

The lawsuit notes that Rauner issued his order at the same time that negotiations for a new contract were beginning between members of the governor’s administration and the American Federation of State, County and Municipal Employees Council 31. AFSCME is Illinois’ largest state employee union, and its contract is set to expire June 30.